重庆市森林工程综合价值评价研究

依据重庆市森林资源清查数据以及重庆市森林工程规划,运用国内外森林资源价值评估领域先进的评估方法,评价了2008年、2008～2010年重庆市森林工程新造林成林后以及2012年森林工程完成规划造林成林后重庆市森林资源综合价值。通过对森林物质产品、生态服务和社会效益的评价,分析了重庆森林工程创造的森林财富为人们带来的福利效益。研究表明,2008年重庆市森林生态系统年产出为750.90亿元;2008～2010年重庆市森林工程新造林成林后,在2008年的基础上每年可增加183.89亿元,全市森林生态系统年产出将达到934.79亿元;2012年森林工程完成规划造林成林后,在2008年的基础上每年可增加271.14亿元,全市森林生态系统年产值将达到1 022.04亿元。     

浅析“十一五”国家科技计划课题财务验收相关问题

课题财务验收是以课题预算书、课题结题审计报告和课题财务验收申请报告及相关经费管理制度为依据,对课题经费管理和使用情况进行评价。财务验收是课题验收的前提,财务验收结果是课题绩效评价的重要组成部分,是今后课题立项和预算安排的重要参考依据。文章针对课题财务验收中涉及的要点,分析了"十一五"国家科技计划课题财务验收的几个问题。     

生物技术在农业中的应用

农业是生物技术研究和应用最直接最广阔的领域。我国农业生物技术的研究自７０年代开始，２０多年来已在细胞工程、胚胎工程、动植物基因工程育种方面取得了突出的研究和应用成果，有的已达世界先进水平。世界生物技术的迅猛发展已首先在医药、食品、农业三大领域内建起了新型产业，并必然导致世界产业结构及科研体制的巨大变革。     

Emergence of anoxia in the California current large marine ecosystem

Eastern boundary current systems are among the world's most productive large marine ecosystems. Because upwelling currents transport nutrient-rich but oxygen-depleted water onto shallow seas, large expanses of productive continental shelves can be vulnerable to the risk of extreme low-oxygen events. Here, we report the novel rise of water-column shelf anoxia in the northern California Current system, a large marine ecosystem with no previous record of such extreme oxygen deficits. The expansion of anoxia highlights the potential for rapid and discontinuous ecosystem change in productive coastal systems that sustain a major portion of the world's fisheries.     

A global map of human impact on marine ecosystems

The management and conservation of the world's oceans require synthesis of spatial data on the distribution and intensity of human activities and the overlap of their impacts on marine ecosystems. We developed an ecosystem-specific, multiscale spatial model to synthesize 17 global data sets of anthropogenic drivers of ecological change for 20 marine ecosystems. Our analysis indicates that no area is unaffected by human influence and that a large fraction (41%) is strongly affected by multiple drivers. However, large areas of relatively little human impact remain, particularly near the poles. The analytical process and resulting maps provide flexible tools for regional and global efforts to allocate conservation resources; to implement ecosystem-based management; and to inform marine spatial planning, education, and basic research.     

Colonization lessons from a tropical forest

The decade-old Transamazon Highway provides a useful stage for examining some of the major issues related to frontier conquest and the impact of pioneer settlement on one of the world's richest biomes. The highway project is an ambitious colonization scheme and the lessons that can be drawn from it, ranging from the environmental effects of stripping back the tree cover to the spread of diseases, will be useful in guiding development policy in other tropical regions.     

ECOSYSTEM ASSESSMENT: Ecologists Hope to Avoid the Mistakes of Previous Assessment

For ecologists, an attempt to assess the world's ecosystems (see main text) has a familiar ring to it. A few years ago, many of the same scientists poured their energy into the Global Biodiversity Assessment. But that exercise sank without a trace after participants failed to find a receptive audience.     

Re-examining Geos Neighbourhood for Its Energy Self-sustained Ability Through Ecological Footprints,Net Energy,and Life Cycle Assessment Tools

There are mounting evidences that human consume significant quantities of resources and have a major impact on the environment. Some research indicates that since the 1980 s human demands on the biosphere have exceeded its regenerrative capacity. One way to solve this problem is to minimize the inappropriate exploitation from environment.This essay will focus on energy self-sustained project, which is a specific way to reduce energy requirements. Energy self-sustained project refers to that energy production is equal to the amount consumed. Three concepts are quoted in the following to assess whether the project achieve zero-energy or not. First, ecological footprint, which provides an indication of the human load on the biosphere, is utilized to measure the inputs and outputs of the bioregion, which is also beneficial for defining the potential energy. Another one is life cycle assessment, which evaluates environmental load that relates to the entire life periodic system of a product, is helpful to measure the products used in the energy self sustained project. In addition, net energy, and gross resource abundance, definitions for selection, or hierarchy of different energy resources, can evaluate the new energy resources in project.Geos Neighbourhood, located in colorado, was planned as the largest net-zero energy neighbourhood in the United States. To meet the energy self sustainability,earth and sun power completely sustain the community's energy needs, and replace all fossil fuels. Compared with the traditional communities, Geos Neighbourhood minimize the adverse impact on the environment. As tools for assessment,ecological footprint, life circle assessment, and net energy, are all used to analyse the planning and design principles in the neighbourhood. By the research, the design principles and energy use in Geos Neighbourhood will be re-examined that whether the zero energy project achieves the reduction of ecological footprint, and energy self sustainability. In addition, life circle assessment will re-examine the materials used in the community also. Finally, the concept of ‘net energy' will test solar energy and earth power which is the major energy used in Geos Neighbourhood.     

Demography. A billion and counting: China's tricky census

Census officials are trying to keep politics out of the world's biggest enumeration as for the first time they gather additional data on mobility, fertility, and other sensitive demographic indicators. The government has repeatedly proclaimed that the information will remain confidential and that the census won't be used as an excuse to send migrants back to their hometowns, but rising expectations of privacy have become a problem for the government in this year's enumeration. More than accuracy is at stake: The wrong numbers could have political ramifications if they raise questions about compliance with such policies as the one-child-per-family rule.     

The impact of conservation on the status of the world's vertebrates

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.     

土地整理项目规划设计环境影响评价

随着社会经济的发展,土地利用形式和结构渐趋复杂,由此引发的生态环境脆弱度也愈加剧烈,土地整理过程是人为对土地生态系统进行干扰,使生态环境的不确定性增大。为了使土地整理区域景观功能更加合理,生态系统更加稳定,提出对土地整理项目规划设计进行环境影响评价,并对环境影响评价的方法、评价指标体系、评价模型等进行了初步探索,以江苏省仪征市某土地整理项目规划设计的环境影响评价为实证。     

融合关联挖掘与D-ANP的数字经济下消费潜力多模态评估模型构建

[目的/意义]当前数字经济下消费潜力评估作为一项复杂的系统工程，未充分考虑评估指标间关联关系，存在效率低、过于依赖专家主观经验等问题，影响消费潜力评估结果的科学性、合理性。[方法/过程]基于广西中烟工业有限责任公司消费潜力相关数据，采用Apriori算法筛选评估指标，融合DEMATEL和ANP分析指标间依赖关系、计算组合权重，构建包含用户价值、营销传播效果、市场影响能力三维度的数字经济下消费潜力多模态评估模型。[结果/结论]以广西中烟工业有限责任公司2021年3月至9月期间6个真龙卷烟产品营销活动为案例进行实证研究，3月、4月、5月、6月营销活动综合得分分别为0.53、0.52、0.51、0.48，消费潜力总体评估结果为“中等”水平，8、9月营销活动优于3～6月，综合得分为0.57、0.63，处于“中等偏上”水平，总体来看市场影响能力、用户价值、营销传播效果方面对消费潜力的影响依次降低。分析结果与实际情况相符程度较高，验证了消费潜力多模态评估模型的可行性和应用性。     

基于物元分析模型的土地整理生态环境影响评价

【目的】评价土地整理项目整理前、后对生态环境的影响,旨在为今后土地整理工作中减少对生态环境的破坏提供经验。【方法】参考生态环境影响评价的相关指标体系,根据土地整理项目相关标准,从水、土壤、生物和社会环境4个生态要素中,选取了11个指标构成土地整理生态环境影响评价的指标体系。在物元分析理论的基础上,采用改进层次分析法确定指标权重,构建了土地整理生态环境影响评价的物元模型,并采用该模型对开原市庆云堡镇土地整理项目进行了评价。【结果】利用构建的土地整理生态环境影响评价物元模型,对开原市庆云堡镇土地整理项目的评价显示,土地整理后项目区的生态环境等级为“较好”,较土地整理前的“一般”等级有很大提升;土地整理项目区的生态环境得到了很大改善,水量供需能力和灌溉保证率得到提升,水土流失得以控制,人均耕地面积增加,中低产耕地面积减少,土壤肥力和生物多样性得到改善,系统抗灾能力增强。【结论】评价结果与实际情况基本相符,说明基于改进层次分析法的物元分析模型在用于土地整理生态环境影响评价时具有一定的可靠性。     

基于ArcGIS Engine的龙凤溪污染状况信息系统的设计与实现

针对研究区内需要的数据量大、数据种类与格式复杂的特点,利用国际上最先进的ArcGIS Engine技术和Visual C#2005开发平台,建立了龙凤溪污染状况查询分析信息系统,将空间数据库与属性数据库集成,实现了空间数据的分析、图文双向查询、图表自动生成以及数据库管理等多种功能,为龙凤溪水污染的治理与防治,水资源、环境生态等领域的研究、管理和决策提供空间信息的统计信息等综合信息服务。     

Telescopes and automation

In stellar astronomy, the future of automation techniques lies in their application to the largest telescopes. In such a case, the cost of automation is small compared to that of the telescope project as a whole, and is well repaid in the savings in observing time. A "stand-alone" capability for manual operation in event of computer breakdown is usually provided for systems like this; an example is the 107-inch (272-cm) telescope under construction at the McDonald Observatory of the University of Texas, which will be associated with an IBM 1800 computer.     

种养循环农作制度碳足迹评估——以鲜食玉米-奶牛-粪便还田循环模式为例

【目的】基于农业碳计量学方法对种养复杂系统全生命周期固碳减排效果的综合评估,是从全产业链视角开展我国低碳农作制度设计和优化的基础。本研究比较了5种系统情景及其对应的种养循环产业链碳足迹评估框架,以期为国内外低碳农作制度创建提供科学、合理、可用的方法学借鉴。【方法】研究基于ISO 14040发布的产品全生命周期碳足迹评价框架,结合IPCC提供的农田和养殖业温室气体核算体系,在不同的系统边界下,构建种养循环农作制度碳足迹评估框架,并以华南热作区鲜食玉米-奶牛-粪便还田循环模式为实证研究对象开展评估效果验证。【结果】评估框架明确了种养循环和分离模式全产业链都包含有农资投入、农田种植、动物养殖、粪便管理、运输和土壤碳汇变化等6个核算环节,并对各环节的碳计量学逻辑及其碳足迹核算方法进行了分析。案例结果表明,鲜食玉米-奶牛-粪便还田种养循环模式全生命周期碳足迹比分离模式降低了34.44%,表现出更好的固碳减排效果。评估框架对种养“耦合”或“脱耦”后对上游农资生产及运输环节的“间接排放”,以及下游产业链饲料替代和废弃物循环利用的“替代性减排”特征能够充分体现,实景系统田间实测数据和调研数据与背景系统...     

浅水湖泊生态系统稳态转换的阈值判定方法

浅水湖泊生态系统对人类干扰的反应会随着干扰力度的改变或增强而出现突然的变化,即发生稳态转换;对其机理和驱动机制的揭示将有助于对湖泊富营养化的控制及恢复。基于"多稳态"理论的稳态转换研究已广泛开展,但对浅水湖泊生态系统稳态转换的驱动机制结论各异,采用的阈值判定方法相差很大,主要有实验观测、模型模拟和统计分析3种。实验观测多关注少数特定指标,指标筛选过程复杂且工作量大;模型模拟虽能从较为全面的尺度上理解生态系统稳态变化的特征和主要机理过程,但在模型误差和不确定性的处理等问题上尚存在不足;统计分析方法基于对长时间序列数据的统计变化规律分析,用以判断或者预警稳态转换现象的发生,是目前最为常用的方法。目前稳态转换领域的研究大都是对已发生的稳态转换进行机制分析或过程反演,对未来预测与预警的问题仍然亟需加强。     

大兴安岭过火区不同森林生态系统碳储量的变化

以1987年"5.6"森林大火过火区6种不同森林生态系统类型为研究对象,采用标准木法和收获法,分析不同生态系统在火干扰27 a后的植被碳储量。结果表明:不同森林生态系统类型的植被碳储量存在差异,相同森林群落类型中不同组分的植被碳储量差异也较大,其中乔木层和凋落物层是森林植被碳储量的主要贡献者;6种不同森林生态系统在火烧干扰27 a后的植被碳储量为23.17~54.06 t/hm^2,碳储量由大到小的顺序为兴安落叶松人工林、樟子松次生林、兴安落叶松次生林、樟子松人工林、白桦次生林(沟谷)、白桦次生林(坡中);植被碳储量恢复度从大到小的依次为兴安落叶松人工林、白桦次生林(沟谷)、白桦次生林(坡中)、兴安落叶松次生林、樟子松次生林、樟子松人工林,分别恢复到同林型成熟林分的49%、43%、36%、35%、33%和25%;兴安落叶松人工林碳储量最高,恢复效果最好。不同森林生态系统类型碳储量与其对应的成熟林碳储量的巨大差异,说明随着森林生态系统的恢复将继续积累大量生物量碳,具有潜在碳汇效应。     

Stabilization wedges: solving the climate problem for the next 50 years with current technologies

Humanity already possesses the fundamental scientific, technical, and industrial know-how to solve the carbon and climate problem for the next half-century. A portfolio of technologies now exists to meet the world's energy needs over the next 50 years and limit atmospheric CO2 to a trajectory that avoids a doubling of the preindustrial concentration. Every element in this portfolio has passed beyond the laboratory bench and demonstration project; many are already implemented somewhere at full industrial scale. Although no element is a credible candidate for doing the entire job (or even half the job) by itself, the portfolio as a whole is large enough that not every element has to be used.